1. Field of the Invention
The present invention relates generally to electrical connectors, and particularly to an angularly adjustable crossover for overhead electric trolley lines.
2. Description of the Related Art
Electrically powered trolley buses or trolleys are commonly provided for public transportation in many cities and other areas of the world. Electric trolleys have a number of advantages, e.g., economical operation, low noise, low pollution, rider convenience, and others. One of the few significant disadvantages of such electric trolleys is the need to provide electrical power from some external source, as the carriage of internal electrical storage batteries is impractical in such an operation.
Accordingly, electrically powered trolleys receive their power either from underground electrical cables or overhead electrical cables, with overhead electrical cables likely being the more common installation due to the relative ease of installation. In either case, some provision must be made for the electrical power cables or lines to cross one another in any but the simplest routing structure.
This is conventionally accomplished by a specially manufactured crossover that connects two lines of one route with two lines of another route, i.e., four electrical lines are connected together to form two continuous lines with the two lines at some angle to one another. Typically, the two continuous lines are at 90 degrees to one another due to the typical square or rectangular city block configuration of most cities, and most such crossovers are manufactured accordingly. However, in many cases the two electric lines cross at some angle other than 90 degrees and a specially manufactured crossover must be provided, with corresponding additional expense for such a specially manufactured unit.
A number of mechanical switches and electrical crossovers have been developed in the past. An example of such is found in Soviet Patent Publication No. 1159811 published on Jun. 7, 1985 to Ni Pi Gorodskogo Passazhirskog. This reference appears to describe (according to the drawings; no English abstract or translation was provided) an adjustable crossover for two or more intersecting lines.
Another example is found in Soviet Patent Publication No. 1477583 published on May 7, 1989 to Ni Pi Gorodskogo Passazhirskog. This reference describes (according to the drawings and machine generated English translation) a multiple line crossover with the various lines being electrically insulated from one another.
Thus, an adjustable crossover for electric trolley lines solving the aforementioned problems is desired.